The interpositus
nucleus projects to the contralateral red nucleus via
the superior cerebellar peduncle. The ruber can then
influence the contralateral spinal cord via the
rubrospinal projection. Compared to the dentate, the
interpositus influences the motor system more quickly. The
interpositus also projects to cells in VA/VL, which in turn
project directly to MI for any correction that is needed.
The cells in VA/VL that project to PM and SMA receive input
from the dentate, while those that project to MI receive
their input from interpositus.